This Program provides research training for young surgeons who plan careers for patient care and investigation in surgical problems of the alimentary tract. Its primary purpose is to prepare these individuals to become independently funded investigators. The program provides intensive, coordinated research training in fundamental aspects of molecular and cell biology, biochemistry and biophysics, organ physiology and pathophysiology, and immunology, as they apply to diseases of the alimentary tract, hepatobiliary system and pancreas. First funded in 1997 as a collaboration between the Departments of Surgery at the Brigham and Women's Hospital and the former Beth Israel Hospital, this program is now expanded to include NIH-funded surgical research laboratories at all major adult teaching hospital affiliates of Harvard Medical School. Current areas of investigation by core preceptor group include: 1) gastro-intestinal mucosal secretion and barrier function (Soybel, Hofer, Hagen); 2) energetics and metabolic derangements of liver in sepsis and shock (Fischer, Hasselgren); 3) gut differentiation and growth responses to starvation or massive resection (Hodin, Ashley, Zinner); 4) cell biology and pathophysiology of acute and chronic pancreatitis (Warshaw); 5) molecular basis of pancreatic cancer growth and metastasis (Callery); 6) tissue engineering as applied to reconstruction and rehabilitation of the alimentary tract (Vacanti, Whang); and 7) evaluation of outcomes and introduction of new technologies in operations on the Digestive System (Zinner, Warshaw, Daley). In addition, a number of young faculty have been recruited to the different Departments of Surgery at HMS, with intention of their development as surgeon-investigators in the field of GI and HPB Surgery. We propose to include these young faculty, under clearly specified circumstances, as co- mentors of our research fellows, thereby enhancing the environment for learning and providing an environment of mentoring for future mentors. The program will be enriched by opportunties for formal coursework in basic sciences and experimental techniques at Harvard's Medical School and School of Public Health, by interactions with core labs and investigators of the NIH-funded Digestive Diseases Centers (HMS-based and MGH-based), and by participation in clinical and research conferences offered at each institution. The training Program Executive Committee (Soybel, Hodin, Hasselgren) oversees selection of trainees, designation of precptors, prescription of formal coursework, and participation of trainees in programs teaching ethics and responsible conduct in research. Trainees are selected through a process open to surgical residents or fellows in accredited U.S. Surgical Residency Training Programs. A pro-active process for seeking applications from individuals belonging to under-represented minority groups is coordinated through the Offices for Diversity at HMS and each of the participating institutions.